Means for rolling up tubular fabric produced by a circular knitting machine

ABSTRACT

A fabric take-up roll is mounted on a rotatable platform beneath a circular knitting machine. A hydraulic circuit rotates the platform in synchronism with the machine about an axis parallel to the longitudinal axis of the fabric tube. The take-up roll is rotated about its own axis at a speed which maintains a predetermined tension in the fabric.

0 United tates Patent 1191 1111 3,842,627 Bassist Oct. 22, 1974 MEANS FOR ROLLING UP TUBULAR 2,366,462 1/1945 Sirmay 66/149 R FABRIC PRODUCED BY A CIRCULAR 2,586,470 2/1952 Lawson 66/149 R 2,932,182 4/1960 Lawson KNITTING MACHINE 3,158,013 11/1964 Monday [75] Inventor: Rudolph G. Bassist, Lancaster, Pa, 3,415,081 12/1968 Anderson 66/151 [73] Assignee: Travis Mills Corp., New York, NY.

a part interest Primary Examiner-W. C. Reyno1ds Assistant Examiner-Andrew M. Falik [22] Flled' May 1973 Attorney, Agent, or FirmBreitenfe1d & Levine [21] Appl. No.: 358,179

Related US. Application Data [63] Continuation of S61. NO. 845,143, July 28, 1969, [571 ABSTRACT abandoned.

A fabric take-up r011 15 mounted on a rotatable plat- 52] us; c1. 66/151 form beneath a circular knitting machine- A hydraulic [51] Int. CL... D04b 15/88 circuit rotates the platform in Synchronism with the [58] Field of Search H 66/56 149 R 151 152 machine about an axis parallel to the-longitudinal axis 66/153. 26/55 R 7 of the fabric tube. The take-up roll is rotated about its own axis at a speed which maintains a predetermined 56] References Cited tens1on 1n the fabr1c.

UNITED STATES PATENTS 11 Claims, 4 Drawing Figures 2,280,472 4/1942 Bromley et a1. 66/153 PMENKWZW 3.842.627

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32 I 33 72 H v" N 26 A, L. Ann,

PAIENKB OCT 2 21974 INVENTOR Pupaz PA/ 6. 5455/57 MEANS FOR ROLLING UP TUBULAR FABRIC PRODUCED BY A CIRCULAR KNITTING MACHINE This application is a continuation of application Ser. No. 845,143, filed July 28, 1969 and now abandoned.

This invention relates to circular knitting machines or so-called double-knit machines, and more particularly to means for rolling up the tubular knit fabric produced by such machines.

Conventionally, such machines are equipped with take-up rolls supported within the base of the machine frame. This arrangement operates satisfactorily, but the capacity of these take-up rolls is necessarily limited, e.g., 40 to 60 yards of fabric, requiring that the machine be stopped frequently to permit withdrawing fabric from the roll. Furthermore, since long pieces of fabric are more advantageous than shorter pieces, from the point of view of further processing of the fabric, the cut pieces of fabric are often sewn together preparatory to further processing.

It is an object of the present invention to overcome these problems by providing a fabric take-up means supported independently of the knitting machine, so that its capacity is theoretically unlimited, and as a practical matter many times greater than conventional take-up rolls.

It is another object of the invention to provide a fabric take-up means rotatable in synchronism with the circular knitting machine with which it is associated, to avoid twisting the fabric portion extending between the machine and the take-up means.

It is a further object of the invention to provide means for discontinuing operation of the take-up means and the knitting machine should the take-up means and knitting machine move more than a predetermined amount out of synchronism.

It is an additional object of the invention to provide a fabric take-up means which winds the fabric at a controlled rate so as to maintain tension in the fabric between prescribed limits.

To accomplish these objectives, the present invention contemplates eliminating the usual take-up roll from the knitting machine and supporting the roll apart from the machine for rotation about two mutually perpendicular axes. One of these axes is the longitudinal axis of the roll, about which the roll rotates to wind up the fabric tube, in flattened condition, as it emanates from the knitting machine. As it moves from the knitting machine to the take-up roll, the fabric passes over a tension bar which controls the speed of take-up, so that the fabric is rolled up at about the same rate at which it is produced.

As is known, in circular knitting machines, the vertical annular needle bed rotates while the machine is in operation with the result that the fabric tube produced rotates about its longitudinal axis. Consequently, unless the take-up roll is rotated in synchronism with the tube, i.e., with the needle bed, about an axis parallel to the longitudinal axis of the tube, the fabric will become twisted in the region between the machine and the take-up roll. According to this invention, the take-up roll support, which may include a platform, is rotated about an axis perpendicular to the axis of the roll and parallel to the axis of the fabric tube. A hydraulic circuit including a variable speed pump and a motor causes rotation of the roll support, and a synchronizing means responsive to rotation of the knitting machine adjusts the speed of the pump so that the roll support rotates at approximately the same speed as the fabric tube. Additionally, electrically-operated valves control flow of fluid through the hydraulic circuit, to make fine adjustments in the rotational speed of the roll support, and electrical circuits for controlling the valves include cooperable contacts carried by the knitting machine and roll support.

Additional features and advantages of the invention will be apparent from the following description in which reference is made to the accompanying drawings.

In the drawings:

FIG. 1 is a diagrammatic elevational view of acircular'knitting machine associated with a fabric take-up means according to this invention;

FIG. 2 is a fragmentary perspective view, on an enlarged scale, of the fabric take-up means and associated fabric-tension controlling means;

FIG. 3 is a fragmentary perspective view of the fabric take-up means showing the synchronizing mechanism; and

FIG. 4 is a fragmentary perspective of an alternative portion of the synchronizing mechanism.

The circular knitting machine 10 of FIG. 1 is conventional in that it includes an annular needle bed in the region 11. As the machine 10 operates, the needle bed is rotated about the vertical centerline of the machine, via a rotating main gear 12, and a knitted fabric tube 13 is produced. During continued operation of the knitting machine, the length of the fabric tube 13 of course increases, and usually the tube is wound, in flattened condition, upon a take-up roll located within the lower part of the knitting machine frame 15. According to the present invention, the conventional take-up roll is replaced by a take-up means of unique character. However, the usual nip rollers (not shown) for feeding the knitted fabric from the machine to the take-up roll preferably remains.

As illustrated in FIG. 1, the fabric take-up means 16 of this invention is supported independently of the knitting machine 10. For example, the take-up means 16 may be arranged on one floor 17 of a building, and the machine frame 15 may be arranged on the floor 18 above, the latter floor being provided with an opening 19 through which the tubular fabric 13 may pass from the machine 10 to the take-up means 16.

The take-up means 16 is illustrated in detail in FIGS. 2 and 3 and includes, in the present illustration of the invention, a circular platform 22 rotatably mounted on the floor 17 by means of a central support 23 (FIG. 1). Fixed to the upper face of platform 22 are a pair of standards 24 (FIG. 2) between which a fabric take-up roll 25 is joumalled. As the take-up rotates about its longitudinal axis, the fabric tube 13 is wound upon itself, in flattened condition, to form a fabric roll 13'. For effecting rotation of the roll 25, a worm wheel 26 is fixed to one of its ends, the wheel 26 meshing with a worm 27 rotated by an electric motor 28 via a variable speed transmission 29 of conventional type. The motor and transmission are mounted on platform 22, and the end of worm 27 opposite transmission 29 is journaled in a bracket 30 fixed to platform 22.

Take-up roll 25 should, of course, rotate at an appropriate speed for winding up fabric 13 at an average linear speed equal to that at which the fabric is produced by the knitting machine 10. This is accomplished by cooperation of the variable speed transmission 29 with a tension bar arrangement. The latter includes a pair of horizontal rods 32 and 33 connected at their ends and pivotally supported by pins 34 between the standards 24 at a location above the take-up roll 25. A link 35, fixed to one pin 34, is pivotally connected to the control lever 37 of the variable speed transmission 29. A tension spring 38 extends between link 35 and platform 22 and tends to move lever 37 downwardly to increase the speed of rotation of worm 27 and hence of take-up roll 25. The spring action is resisted by the fabric 13 threaded under rod 32 and over rod 33 of the tension bar. Thus, if the take-up roll is rotating too slowly, excess slack will exist in fabric 13 and spring 38 is free to adjust transmission 29 to increase the speed of roll 25. Conversely, if the take-up roll is rotating too fast, tension will build up in fabric 13 causing rotation of tension bar 32, 33 in a direction which lifts link 35 and hence lever 37. The result is a decrease in speed of roll 25.

As mentioned above, the needle bed of the machine rotates about the vertical centerline of the machine, along with main gear 12, and hence the fabric tube 13 rotates about its longitudinal axis. Thus, if the take-up roll were to remain stationary with respect to a vertical axis, the fabric 13 would become twisted in the region between the machine 10 and the roll 25. For this reason, the take-up roll is mounted on rotatable platform 22, and a synchronizing means is provided for rotating the platform in synchronism with rotation of the main gear 12 and hence in synchronism with rotation of fabric tube 13. In this way, twisting of the fabric is avoided.

The synchronizing means, illustrated in FIG. 3, includes a hydraulic circuit having a hydraulic motor 41 carrying a sprocket wheel 42 on its output shaft. Platform 22 is formed with sprocket teeth around its periphery, and a chain 43 meshing with these sprocket teeth and wheel 42 transmits rotary motion from motor 41 to platform 22. An idler sprocket wheel 44 maintains tension in the chain 43. The motor 41 receives hydraulic fluid from a variable speed hydraulic pump 46, of conventional design, operated by an electric motor 47. Pump 46 draws hydraulic fluid from a reservoir 48, via a filter 49, through conduit 50, and delivers the fluid through a conduit 51 to motor 41. The fluid returns to reservoir 48 from motor 41 through conduits 52 and 53.

Adjustment of the speed of pump 46, to insure that motor 41 rotates platform 22 at the same speed as main gear 12, is accomplished by means of a differential 56. The output shaft of differential 56 carries a pulley 57 connected by a belt 58 to a pulley 59 carried by the speed control mechanism of pump 46. Thus, any movement of the differential output shaft is transmitted via a suitable transmission, indicated generally by reference numeral 61, to input shaft 62 of differential 56. The other input to the differential is received from sprocket wheel 63 meshing with chain 43. Since the diameter of platform 22 is larger than the diameter of main gear 12, motion of wheel 63 is applied to thedifferential 56 via a suitable gear reduction 64, so that this input to the differential corresponds to what it would be if the platform 22 had the same diameter as main gear 12.

FIG. 4 illustrates a way in which gear reduction 64 can be eliminated. The height of standards 24 are increased with respect to the height shown in FIG. 2, and secured to the upper ends 24 of the standards is a ring 65 equal in diameter to the main gear 12. In place of sprocket wheel 63, a roller 66 engages the ring 65 and is rotated by the ring as the platform rotates. Via suitable transmission means 67, rotation of roller 66 is applied to differential 56. Since the diameter of main gear 12 and ring 65 are equal, no compensating means, such as a gear reduction train, is needed.

It will be appreciated that if the main gear 12 and platform 22 are rotating at precisely the same speed, the inputs to the differential 56 will be identical and there will be no output. Hence, the speed of pump 46, and hence the speed of motor 41, remains constant. Should the rotational speed of the platform become different from the rotational speed of the main gear, the inputs to the differential will be different thereby producing a differential output causing adjustment of the speed of pump 46 in a manner to bring the speed of platform 22 into synchronism with the speed of main gear 12.

It has been found that although the synchronizing mechanism as thus far described is adequate for accomplishing coarse synchronization, a means for making fine adjustments is desirable. For this purpose, two electrically controlled, e.g., solenoid operated, valves 70 and 71 are arranged in conduit 51 between pump 46 and motor 41. Valve 70 is normally wide open but can be partially closed to reduce flow of hydraulic fluid through conduit 51, and simultaneously bleed part of the fluid from pump 46 into conduit 53 for direct return to reservoir 48. Valve 71 is normally partially closed and bleeds part of the fluid from pump 46 into conduit 53, but can be fully opened to increase hydraulic fluid flow through conduit 51. For controlling the valves, a standard 72, mounted on platform 22, carries a pair of slightly spaced-apart metal bars 73 and 74, the space between the bars being bridged by an insulator piece 75. A metal arm 76, carried by the main gear 12 of machine 10 (see also FIG. 1), terminates at its lower end in yoke formation which slidably engages insulator piece 75. A flexible electrical conductor 77 connects arm 76 to a source of power, indicated by the reference numeral 78, a conductor 79 connects bar 73 to the electrical operator of valve 70, and a conductor 80 connects bar 74 to the operator of valve 71.

Should platform 22 begin to rotate faster than main gear 12, bar 73 will slide into engagement with arm 76, thereby completing an electrical circuit from source 78, through conductor 77, arm 76, bar 73, conductor 79, and valve 70 to ground. As a result, valve 70 is actuated and closes partially to reduce fluid flow to motor 41 and bleed some fluid to reservoir 48. Hence, platform 22 slows down, and when arm 76 again engages insulator 75, the electrical circuit is opened. On the other hand, should platform 22 begin to rotate slower than main gear 12, bar 74 will slide into contact with arm 76, thereby completing a circuit from source 78, through conductor 77, arm 76, bar 74, conductor 80, and valve 71 to ground. As a result, valve 71 is actuated and opens fully to increase fluid flow to motor 41 and reduce bleeding of fluid to reservoir 48. Hnece, platform 22 speeds up, and when arm 76 again engages insulator 75, the circuit opens.

As a safety precaution, bars 73 and 74 carry normally open limit switches 83 and 84, respectively, and an electrically operated, normally open, shut off valve 85 is arranged in conduit 52, between hydraulic motor 41 and reservoir 48. Should platform 22 move far enough out of synchronism with main gear 12 to bring arm 76 into engagement with, and thereby close, either limit switch 83 or 84, a circuit is completed from source 78, through the closed switch, conductor 86, and valve 85 to ground. As a result, valve 85 closes, stopping motor 41 and platform 22 immediately despite the inertia of the fluid in the hydraulic circuit. Simultaneously, via circuits not shown, closing of either switch 83 or 84 shuts off electric motors 28 and 47, and the knitting machine 10.

Electrical power to motor 28 on platform 22 is supplied by three concentric rings 89 (FIG. 1) fixed to floor 17 beneath platform 22, which are slidably 'engaged by three wipers 90 depending from the platform. Similarly, the electrical circuits represented by conductors 79, 80 and 86 are completed via three concentric rings 91 fixed to floor 17 beneath platform 22, which are slidably engaged by three wipers 92 depending from platform 22.

The invention has been shown and described in preferred form only, and by way of example, and it is understood, therefore, that many variations may be made in the invention which will still be comprised within its spirit.

What is claimed is:

1. For use with a circular knitting machine which produces a fabric tube, the machine having a stationary frame and drive means for rotating parts of the machine with respect to the frame about its vertical axis, the fabric tube being rotated about its longitudinal axis while the machine is in operation:

a. take-up means for rolling up the flattened fabric tube,

b. means for supporting said take-up means, said support means being outside of the knitting machine frame and being completely independent of and unsupported by the knitting machine frame,

c. drive means for rotating said support means and hence said take-up means about an axis parallel to the longitudinal axis of the fabric tube as it leaves the machine, said drive means (0) being operable independently of the machine drive means, and

d. means responsive to movement of a rotating part of the machine for adjusting the speed of drive means (0) so that the latter rotates support means (b) in synchronism with rotation of the tube about its longitudinal axis, whereby the tube remains untwisted between the machine and said take-up means.

2. The arrangement of claim 1 including means engaging the fabric between the machine frame and means (a) for adjusting the speed of means (a) as it rolls up the fabric tube so as to maintain a predetermined tension in the fabric as it moves from the machine to means (a).

3. The arrangement of claim 1 wherein said means (a) includes a take-up roll rotatable about an axis perpendicular to the longitudinal axis of the fabric tube as it leaves the machine, and a motor for rotating said roll.

4. The arrangement of claim 3 including a pivotally mounted tension bar which the fabric tube slides past during its movement from the machine to said roll, the position of said tension bar depending upon the tension in the fabric tube, and means responsive to the position of said tension bar for controlling the speed of said motor. a

5. The arrangement of claim 1 wherein said support means includes a platform supporting said means (a), said platform being rotated by said means (c).

6. The arrangement of claim 1 wherein said means (c) includes a hydraulic motor, and said means (d) includes a hydraulic circuit-for energizing said hydraulic motor.

7. The arrangement of claim 6 wherein said hydraulic circuit includes means responsive to the difference in rotational speeds of the machine and said means (b) for controlling the speed of flow of hydraulic fluid to said hydraulic motor.

8. The arrangement of claim 7 wherein said lastnamed means includes a variable speed hydraulic pump for delivering hydraulic fluid to said hydraulic motor, and including a differential, means for applying to said differential as separate inputs to the latter the speed of rotation of the machine and the speed of rotation of said means (a), and means for applying the output of said differential to said pump to vary the rate at which the latter delivers fluid to said hydraulic motor.

9. The arrangement of claim 7 wherein said lastnamed means includes a pair of electrically operated valves, said valves serving when actuated to respectively increase and decrease flow to said hydraulic motor, and including an electric energizing circuit for each of said valves, a pair of spaced-apart contacts movable with one of said means b) or said machine, one of said contacts being in each of said electric circuits, a single electric-contact movable with the other of said means (b) or said machine, said single contact being between said pair of contacts and serving upon engagement with either of said pair to complete the circuit for energizing its respective valve.

10. The arrangement of claim 7 wherein said lastnamed means includes a variable speed hydraulic pump for delivering hydraulic fluid to said hydraulic motor, and a pair of electrically operated valves, said valves serving when actuated to respectively increase and decrease flow to said hydraulic motor, and including 1. a differential, means for applying to said differential as separate inputs to the latter the speed of rotation of the machine and the speed of rotation of said means (b), and means for applying the output of said differential to said pump to vary the rate at which the latter delivers fluid to said hydraulic motor, and

II. an electric energizing circuit for each of said valves, a pair of spaced-apart contacts movable with one of said means (b) or said machine, one of said contacts being in each of said electric circuits, a single electric-contact movable with the other of said means (b) or said machine, said single contact being between said pair of contacts and serving upon engagement with either of said pair to complete the circuit for energizing its respective valve.

out of synchronism. 

1. For use with a circular knitting machine which produces a fabric tube, the machine having a stationary frame and drive means for rotating parts of the machine with respect to the frame about its vertical axis, the fabric tube being rotated about its longitudinal axis while the machine is in operation: a. take-up means for rolling up the flattened fabric tube, b. means for supporting said take-up means, said support means being outside of the knitting machine frame and being completely independent of and unsupported by the knitting machine frame, c. drive means for rotating said support means and hence said take-up means about an axis parallel to the longitudinal axis of the fabric tube as it leaves the machine, said drive means (c) being operable independently of the machine drive means, and d. means responsive to movement of a rotating part of the machine for adjusting the speed of drive means (c) so that the latter rotates support means (b) in synchronism with rotation of the tube about its longitudinal axis, whereby the tube remains untwisted between the machine and said take-up means.
 2. The arrangement of claim 1 including means engaging the fabric between the machine frame and means (a) for adjusting the speed of means (a) as it rolls up the fabric tube so as to maintain a predetermined tension in the fabric as it moves from the machine to means (a).
 3. The arrangement of claim 1 wherein said means (a) includes a take-up roll rotatable about an axis perpendicular to the longitudinal axis of the fabric tube as it leaves the machine, and a motor for rotating said roll.
 4. The arrangement of claim 3 including a pivotally mounted tension bar which the fabric tube slides past during its movement from the machine to said roll, the position of said tension bar depending upon the tension in the fabric tube, and means responsive to the position of said tension bar for controlling the speed of said motor.
 5. The arrangement of claim 1 wherein said support means includes a platform supporting said means (a), said platform being rotated by said means (c).
 6. The arrangement of claim 1 wherein said means (c) includes a hydraulic motor, and said means (d) includes a hydraulic circuit for energizing said hydraulic motor.
 7. The arrangement of claim 6 wherein said hydraulic circuit includes means responsive to the difference in rotational speeds of the machine and said means (b) for controlling the speed of flow of hydraulic fluid to said hydraulic motor.
 8. The arrangement of claim 7 wherein said last-named means includes a variable speed hydraulic pump for delivering hydraulic fluid to said hydraulic motor, and including a differential, means for applying to said differential as separate inputs to the latter the speed of rotation of the machine and the speed of rotation of said means (a), and means for applying the output of said differential to said pump to vary the rate at which the latter delivers fluid to said hydraulic motor.
 9. The arrangement of claim 7 wherein said last-named means includes a pair of electrically operated valves, said valves serving when actuated to respectively increase and decrease flow to said hydraulic motor, and including an electric energizing circuit for each of said valves, a pair of spaced-apart contacts movable with one of said means (b) or said machine, one of said contacts being in each of said electric circuits, a single electric-contact movable with the other of said means (b) or said machine, said single contact being between said pair of contacts and serving upon engagement with either of said pair to complete the circuit for energizing its respective valve.
 10. The arrangement of claim 7 wherein said last-named means includes a variable speed hydraulic pump for delivering hydraulic fluid to said hydraulic motor, and a pair of electrically operated valves, said valves serving when actuated to respectivEly increase and decrease flow to said hydraulic motor, and including I. a differential, means for applying to said differential as separate inputs to the latter the speed of rotation of the machine and the speed of rotation of said means (b), and means for applying the output of said differential to said pump to vary the rate at which the latter delivers fluid to said hydraulic motor, and II. an electric energizing circuit for each of said valves, a pair of spaced-apart contacts movable with one of said means (b) or said machine, one of said contacts being in each of said electric circuits, a single electric-contact movable with the other of said means (b) or said machine, said single contact being between said pair of contacts and serving upon engagement with either of said pair to complete the circuit for energizing its respective valve.
 11. The arrangement of claim 9 including electric means for preventing flow of hydraulic fluid through said hydraulic circuit, an electric circuit for said electric means, a pair of spaced-apart limit switches in said circuit, said switches being movable with one of said means (b) or said machine, and a switch actuator movable with the other of said means (b) or said machine, whereby one of said switches is operated to actuate said electric preventing means when said machine and means (b) move more than a predetermined amount out of synchronism. 